BY ROBERT HALL. 323 



One genus absent from 6 that is present in areas 4 

 and 5 is Cisticola. Cisticola in emigrating from 4 to 5 

 did not get further south than the Bass Strait Islands. 



Acanthornis is the only passerine genus peculiar to 

 area 5, while Tribonyx is the second peculiar genus. 



Area 6 with its 239 species appears to have been con- 

 structed from areas 4 and 7. It would seem as if it had 

 drawn largely from area 4, then passed many of the 

 species on to area 7, differentiated certain of them there, 

 and had returned to area 6 a part of each of those species. 

 By this means it could make a large list of species. The 

 hawks and parrots so largely represented in area 7 are 

 mostly common to area 6. These are barely represented 

 in area 4, thus making a distinct difference by two im- 

 portant orders between areas 6 and 4. 



Xerophila, Amytornis, Oreoica, Drymsedus, and En- 

 tomophila are not found in area 4, being immigrants 

 from area 7 to 6. 



Eopsaltria, Meliornis, Acanthorhynchus, Pseudogery- 

 gone, and Chibia of area 6 are found in area 4, but not in 

 area 7. All but Chibia continue their westerly course in 

 area 9. 



Origma, Alenura, and Pycnoptilus, of area 4, do not 

 find suitable country in area 6, and are absent from it. 



This area is devoid of strong opposing characters 

 when compared with area 7, but because of the forms 

 that are passing through it and not through area 7, to 

 area 9, it is sufficiently differentiated to be recognised as 

 an avifaunal area. It is here that Lipoa and ^lehura 

 almost meet — birds of the ultra-dry and ultra-moist 

 country respectively. 



Area 7 is the broadest— and the desert area. The 

 relation of Passerine genera and species to the other areas 

 is shown in Table I. It is seen how it is least of all in 

 afBnity with areas 8 and i, and most of all with areas 

 6 and 3. 



The generic relationship of area 7 with the other areas 

 may be shown by stating the principal genera of 7 absent 

 in the areas, as follows: — 



